This invention relates to a perch assembly for a wild bird feeder and more particularly to a perch assembly which discriminates between large and small birds such that large birds will slide off the perch and not be able to gain access to the feed within the feeder while small birds will be able to alight thereon and successfully obtain, feed in the desired manner.
Such previous application describes a bird perch formed of a bendable, tightly wound wire coil having a first end adapted for replaceable mounting in a bird feeder opening. The perch body is adapted to be downwardly bent when a large, that is, heavy, bird attempts to rest thereon and remains generally straight to support small, that is, light, birds resting thereon. This is a particularly desirable feature, and has shown decided operational success in field use. However, inasmuch as it is highly desirable to be able to form the spring coil from a non-corrodible material such as stainless steel, some problems have occurred since stainless steel cannot be adequately heat treated after it is coiled. Therefore, the coil tends to be able to be stretched in use as by a squirrel or other animal over stressing the perch as by pulling. Such action by these large pests can open coil portions such that the intended normal straight lateral extension of the coil away from the feeder wall to which it is attached is impaired.
It would be advantageous to provide coil means that prevent the over stressing of individual coils. One obvious solution would be to use a regular steel that could be adequately heat treated to assure the necessary snap-back of the individual coils once they are elongated but regular steel is subject to undesirable rusting in use conditions or if provided with a rustproof coating necessitates additional handling and expense.
Accordingly, an initial object of the present invention is to provide means by which such a bendable coil bird perch is mechanically maintained against elongating over stresses yet which adquately provides for the main function of the device, that is, the ability of the coil to bend downward when contacted by large birds.
A secondary feature and object of the invention is to provide a bird perch assembly as indicated above which primarily bends evenly throughout its length from its connection with the feeder wall to which it is attached.
These and other objects of the present invention are accomplished by a bird perch assembly adapted for use with wild bird feeders of the type having at least one feed opening extending through a substantially vertically disposed wall thereof, said perch assembly outwardly laterally extending from said wall at a point substantially in line with and beneath said opening, said perch assembly comprising a perch and a keeper device, said perch composed entire of a hollow, straight cylindrical, wound wire coil having individual turns, and being tightly wound with adjacent individual turns touching each other, said coil having first and second terminal ends and an intermediate laterally extending portion with said first terminal end positioned in a perch opening extending into said wall and said second terminal end terminating at a position spaced from said wall, said keeper device having a bendable, non-extendible elongated body laterally extending along said coil and terminating in first and second connectors respectively engaged to said first and second coil terminal ends, that portion of said perch outwardly spaced from said wall being of a diameter easily grasped by perching birds and further being easily bendable such that large birds will cause the wire to bend downward and cause such birds to slide off or fly away as a result of being forced to an insecure or untenable position while small birds will not cause the wire to bend substantially downward.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawing.